std::vector::shrink_to_fit

From Cppreference

Jump to: navigation, search
C++ Standard Library
Containers library
std::vector
void shrink_to_fit();
 (since C++11)

Requests the removal of unused capacity.

It is a non-binding request to reduce capacity to size. It depends on the implementation if the request is fulfilled.

Contents

[edit] Parameters

(none)

[edit] Return value

(none)

[edit] Complexity

Constant

Example

#include <iostream>
#include <vector>
int main()
{
    std::vector<int> v;
    std::cout << "Default-constructd capacity is " << v.capacity() << '\n';
    v.resize(100);
    std::cout << "Capacity of a 100-element vector is " << v.capacity() << '\n';
    v.clear();
    std::cout << "Capacity after clear() is " << v.capacity() << '\n';
    v.shrink_to_fit();
    std::cout << "Capacity after shrink_to_fit() is " << v.capacity() << '\n';
}

Output: 

Default-constructd capacity is 0
Capacity of a 100-element vector is 100
Capacity after clear() is 100
Capacity after shrink_to_fit() is 0

[edit] See also

 returns the number of elements
(public member function)
returns the number of elements that can be held in currently allocated storage
(public member function)
Retrieved from "http://en.cppreference.com/w/cpp/container/vector/shrink_to_fit"
Personal tools
Namespaces
Variants
Actions
Navigation
Toolbox
In other languages